This invention generally relates to collapsible play yard or play pen apparatus, and more particularly to an improved frame construction for such apparatus. An exemplary apparatus in the prior art is described in U.S. Pat. No. 5,381,570 to Cheng, which is incorporated herein by reference in its entirety.
Any apparatus intended for use with babies and children must be designed with safety as the utmost consideration. The typical collapsible playpen is generally comprised of a hinged frame structure adapted to support a foldable enclosure, the frame and enclosure undergoing complementary movements to transform from an expanded, erected disposition in which the apparatus supports a baby or toddler, to a knock-down disposition in which the apparatus occupies a minimum volume for optimum storage and transport.
One potential failure mode of such apparatus occurs when the frame folds up accidentally with a baby or toddler supported within the apparatus. This action may entrap and injure the limbs or neck of the occupant. Accordingly, all reasonable measures must be taken to prevent such occurrences. One device known in the prior art that addresses this problem, described in U.S. Pat. No. 5,542,151, protects the folding joints of the upper frame members from accidental release and collapse due to incidental contact or manipulation by the occupant of the playpen.
However, if the improved folding frame structure is compromised in some unforeseen manner, there is no further protection from accidental collapse of the apparatus. Thus it would be desirable for such prior art apparatus to include a failsafe device that prevents accidental collapse of the apparatus when it is occupied by a baby, toddler or child, without regard to the cause of the accident, whether known or unforeseen.